https://www.selleckchem.com/TGF-beta.html We discuss the mechanism by which the highly conserved FruR regulates the expression of its target operon encoding the highly conserved PTSFru and FruK in a completely opposite direction among closely related families of bacteria.The group A O antigen is the major surface polysaccharide of Salmonella enterica serovar Paratyphi A (SPA), and the focal point for most current vaccine development efforts. The SPA O-antigen repeat (O unit) is structurally similar to the group D1 O unit of S. enterica serovar Typhi, differing only in the presence of a terminal side-branch paratose (Par) in place of tyvelose (Tyv), both of which are attached by the glycosyltransferase WbaV. The two O-antigen gene clusters are also highly similar, but with a loss-of-function mutation in the group A tyv gene and the tandem amplification of wbaV in most SPA strains. In this study, we show that SPA strains consistently produce less O antigen than their group D1 counterparts and use an artificial group A strain (D1 Δtyv) to show this is due to inefficient Par attachment by WbaV. We also demonstrate that group A O-antigen production can be increased by overexpression of the wbaV gene in both the D1 Δtyv strain and two multi-wbaV SPA strains. These findings should be broadly applicable in ongoing vaccine development pipelines, where efficient isolation and purification of large quantities of O antigen is of critical importance. Mild traumatic brain injury (mTBI) is associated with significant financial cost and reduced military readiness and impacts quality of life for active duty service members (SMs). Post-concussive symptoms can include vestibular impairments, such as chronic dizziness and postural instability, which can be compounded by psychological comorbidities like PTSD. Comprehensive vestibular evaluations are required to assess symptoms and guide clinical decision-making. At the National Intrepid Center of Excellence (NICoE), in addition to tradi